Internal combustion engine



Juiy 28, 1936. T. N; SMITH INTERNAL COMBUSTION ENGINE Filed Nov. 7, 19:54 a Sheets-Sheet 1 x M 2M mmmw a 4 July 28, 1936.

-'r. N. SMITH. 2,048,826

INTERNAL COMBUSTION ENGINE Filed Nov. 7, 1934 s sheet-gleet 2 Tia/770s Noah Sin/777,

T. N, SMITH INTERNAL COMBUSTION ENGINE Filed Nov. 7, 1934 3 Sheets-Sheet 3 Fla-8.1

July 28, 1936.

Patented July 28, 1936 STATES ream 3 Claims.

This invention relates in general to internal combustion engines, more particularly to that general type of engines which employ rotary valves for controlling the intake and exhaust ports. It has for a general object to provide a new and improved mechanism for controlling said ports.

This application is a continuation in part of my copending application Serial No. 632,588, filed September 10, 1932.

' The principal object of the present invention is to provide a motor of this general type, of greater efliciency and of simpler and improved design.

Another object is to provide rotary valves for use with engines of this general class which will have more eifective sealing action and which will resist wear and yet permit an extremely large opening of the ports with respect to the size of 2c the rotary valve element used.

Yet another object of the invention consists in the novel means provided for circulating a cooling medium through the valve, the cooling means being, if desired, entirely independent of the general cooling system of the motor.

Still further the invention contemplates the use of a cylinder head of improved design in combination with the improved rotary valves, which comprises a relatively small combustion chamber but yet provides relatively large ports having access thereto.

Many other and further objects and advantages of the invention will become apparent from the following specification when considered in connection with the accompanying drawings,

forming a part thereof.

In the drawings:

Figure 1 is a side elevation of the forward up-' perend of the improved motor with parts broken away to show the mounting of the forward end of one of the rotary valves;

Figure 2 is an end view partly in section showing the drive mechanism for the cam shaft and the rotary valves;

Figure 3 is a side elevation of the portion of the motor shown in Figure 1 with parts further broken away showing the cam shaft and poppet valves;

Figure 4 is a sectional view taken on the line 44 of Figure 3 looking in the direction of the arrows;

Figure -5 is a side view of one of the rotary valves, showing the recess therein and the sealing plate mounted thereon;

' Figure 6 is a side view of the rear end of one of the rotary valve elements with parts broken away, showing the packing gland for connecting one of the ducts for delivering cooling fluid to the valve;

Figure 7 is a sectional view taken on the line '5 l--'l of Figure 5 showing the shape of one of the valve elements at one of the ports therein; and

Figure 8 is a sectional view of a modified form of rotary valve showing a difierent contour of recess.

With more particular reference to the drawings, the specific embodiment of the invention illustrated herein comprises a cylinder block I having a plurality of cylinders 2 formed in line therein. Obviously this block may be one bank of a V type motor as well as the main cylinder block of the conventional form of motor having the cylinders in line. The invention herein disclosed is likewise applicable to opposed, radial, inverted or any cylinder arrangement, and as 20 will be hereinafter seen, may be utilized in a motor employing any type of cooling system. The cylinder block is provided with a water jacket 3 and has mounted thereon a cylinder head 4, secured thereto by means of studs 5 as-is customary'25 in the art. The cylinder head is water jacketed as is conventional, having passageways in communication with the passageways in the cylinder block, in order that the portion of the cylinder around the combustion chamber may at all times 30 be adequately cooled.

The cylinder head is preferably formed of a single casting having a pair of longitudinal cylindrical bores 6 and l therethrougli in which are mounted a pair of rotary valve elements 8 35 and 9. These rotary valve elements are substantially identical in size and construction and will be described in greater detail hereinafter. The valve element 8 serves to control the exhaust from and the valve 9 serves to control the intake 40 to the cylinders. The cylinder head d has laterally disposed exhaust and intake ports ill and II respectively which communicate with the longitudinal bores 6 and 1. Suitable manifolds extend longitudinally of the cylinder block serving 45 the intake and exhaust ports as is customary. The lower side of the cylinder head is recessed adjacent each cylinder to form a combustion J chamber I2 which is connected by a passageway 50 I3 with the bores 6 and I. Flow through the passageway I3 is controlled by means of a pair of valves I5 cooperating with a pair of ports M in the passageway l3. The stems of the poppet valves l5 extend vertically upward through suit- 5 able guides formed in the cylinder head 4 and have washers l6 secured to their upper ends which serve to confine compression springs i1 between the washers and the cylinder head proper, the springs serving to maintain the valves 55 in engagement with their seats, thereby normally maintaining these ports closed. The construction of the cylinder head, ports, valves and other parts adjacent each cylinder are substantially identical in each instance.

The improved rotary valve members 8 and 9 are formed from a cylindrical member of sufficiently large diameter to fit closely within the bores 6 and l, the cylindrical member being hollow throughout its entire length. Inasmuch as these rotary valve members are substantially identical in construction, only the member 8 will be described. This valve is recessed adjacent the port it) which it controls, to form a segmental port 26 of greater than 180". This recess is provided with walls 2| and 22 which prevent communication between the recess 20 and the internal passageway through the valve. These parts may be secured together by welding or in any other conventional manner as long as a heat resistant fluid tight joint is maintained. In the embodiment of the invention illustrated in Figures 1 to 7 of the drawings, it will be seen that the wall 2i is formed of two plane surfaces interduced diameter and has mounted thereon a cy- I lindrically surfaced sealing plate 23, the outer surface of which has a contour formed on a radius the same as the radius of the bores 6 and I.

A pair of short cylindrical tubes 24 extend through holes in the wall of the reduced portion of the valve body and the wall 2| of the recess- 20, and are secured to these walls to provide a fluid tight joint to prevent escape of fluid from the interior of the rotary valve member. The inner ends of the tubes 24 are closed by plugs 25 which maybe welded therein and have their ends lying flush with the surface of the wall 2! of the recess 20. A pair of plungers 26 of cylindrical form and of a diameter sufliciently small to slide freely within the tubes 24 are secured to the inner surface of the cylindrically cylindrical portion on which is mounted the raceway of a ball bearing assembly 30 which is mounted in the cylinder head 4 and serves to mount each of the rotary valve elements'for free rotation. The forward end of each of the rotary valve elements is provided in front of the ball bearings 30 with a conical reduced portion on which are mounted spur gears 3! which serve to drive these valves. Ducts '32 extend axially through the end portions of the valves providing constant communication between a reservoir 33 and the hollow interior of the valve. The rear ends of the rotary valve elements are similarly mounted in ball bearing assemblies 30 and are provided with a packing gland composed of a cylindrical fitting 35 surrounding a cylindrical .extension of the valve element and serving to compress a mass of packing material 36, and held in position by a screw collar 31 threaded on to a cylindrical extension 38 of the cylinder head 4. The fitting 35 has an axially disposed duct therethrough communicating with the interior of the rotary valve element through the duct 30 in the end of the element. The fitting 35 is threaded at its outer end to receive a conduit not shown which may be connected to a convenient source of cooling fluid to be circulated through the valve. In the embodiment of the invention shown in the drawings, the fitting 35 is adapted to be connected to the oil pump of the engine, and the reservoir 33 is connected by a conduit 60 to drain into the crank case of the motor.

In orderto operate the above described valves in synchionism with the crank shaft ofthe engine, a vertically disposed valve driving shaft 42 is mounted in suitable bearings at the forward end of the motor and is geared by means of bevel gears not shown to the crank shaft. The upper end of the shaft 42 has secured thereto a bevel gear 43 which meshes with a bevel series of teeth 44 on a compound gear 45 which is secured to an overhead cam shaft 46, mounted for rota tion in suitable bearings 41. The cam shaft 46 is provided with cams at intervals throughout its length which serve to operate the poppet valves i5, described above. As has been noted heretofore, there are two of the valves I5 provided for each cylinder and .these serve as an auxiliary control for the flow of fluids to and from the cylinder, the principal control being provided by the rotary valves; Therefore, it will be seen that the cams on the cam shaft 46 are provided in identical pairs, one pair for each cylinder in order that each of the valves of the pair will be operated simultaneously.

The compound gear 45, besides being provided with the'series of bevel teeth 44 by which it is driven, is provided with a'series of spur teeth 48 which drive an idler gear 49 mounted in suitable bearings 50 on a stud 5|. The idler gear 49 is in mesh with the two gears 3| secured to the forward ends of the rotary valve elements 8 and 9 in order that these two valve members will be driven at the same speed in the same direction.

It will be seen from the drawings that the ports Ill and H and the passageway are, at the point where they meet the longitudinal bores 6 and 1, substantially rectangular in cross section and that they enter the bores 6 and I tangentially thereto. It is noted further that the narrower dimensions of these portsare slightly less than the radius of the bores 6 and I. As the rotary valves rotate, it will be seen that the recess 20 will periodically come into registry with the passageway l3 and the port [0, thus leaving a straight rectangular passageway from the valves l5 into the manifold. This registry occurs once for every revolution of the valve and therefore the gears driving the rotary valve elements are constructed so that the rotary valve elements 8 and 9 will be driven at one half the speed of the crank shaft. The recess in the exhaust valve is timed to open the port ii approximately one-half a revolution of the valve elements afterthe intake port has closed. The cams located on the cam shaft 46 are so formed and positioned that they serve to actuate the valves l5 to open the ports 54 at about the time the exhaust valve begins to open and maintains these ports open until the intake valve has closed. From this it will be apparent that at the time the charge in the cylinder is compressed, the combustion chamber is eflectively sealed not only by the valves IE but by the sealing plates 23 5 which, due to their resilient mountings, are

forced into engagement with theapertures of the passageway l3 at the points this passageway connects with the bores 6 and 'l.

The rotary valve elements are hollow throughout their entire length, but due to the deep recesses formed therein, the passage therethrough is relatively tortuous, rendering the action of the cooling fluid which is circulated therethrough very effective. Due to the fact that the interiors of the valve elements are completely sealed except for the ducts at the ends of the valves, it will be seen that the fluid which may be used may be enfltirely separate from the regular cooling system. If desired, the ducts may be connected to the regular cooling system to circulate water from the radiator through the valve or may be connected into the lubricating system as described above. A modified form of cross section for the rotary valve elementat the ports is illustrated in Figure 8. In this form it will be seen that the surface which constitutes one wall of the port when the valve is open is curved in such a manner as to form an impeller. One form of such impeller section is shown in Figure 8 although it will be apparent that this section may be substantially modified and yet produce beneficial results. It will be seen that the curvature of this impeller section will, as the valve is rotated, greatly faciliinterior of said valve, a bearing and sealing plate 10 carried by said valve, tubes extending through the hollow portion of said valve, and spring means housed within said tubes for urging said bearing 1 and sealing plate outwardly.

2. In an internal combustion engine, a rotary 15 valve journalled in the engine head, said valve being hollow and provided with means for the circulation of "a cooling fluid therethrough, a bearing and sealing plate mounted upon said valve, tubes extending radially through the hollow 20 portion of said valve and spring means housed within said tubes for urgingsaid bearing and sealing plate outwardly.

3. A rotary valve for internal combustion en- Y gines comprising a hollow, generally cylindrical valve body having a. transverse recess formed therein constituting a port, and also having a space therein for the circulation of a cooling fiuid,

a cylindrically surfaced segmental sealing plate longitudinally co-extensive with said recess but on the opposite side of said valve body, spring means located within the hollow interior of said valve body and serving to resiliently urge said sealing plate radially outward, and means enclosing said spring means and separating the same from said fluid space. v

' THOMAS NOAH SMITH. 

